1. Technical Field
Exemplary embodiments of the present invention relate to an assembly device to mount a plurality of writing heads on a head holder and an assembly method thereof.
2. Background Art
Conventionally, for the purpose of obtaining a longer, denser writing head unit, a writing head unit including a plurality of writing heads disposed in one head holder is known. This type of writing head unit has the advantage that it can be produced inexpensively compared to producing a single long, dense writing head.
A writing head unit configured such that a plurality of ink droplet discharge heads each discharging droplets is mounted to the head holder is known. In such an arrangement, the plurality of droplet discharge heads needs to be positioned precisely at respective predetermined positions of the head holder and securely mounted so that the ink droplets are discharged accurately from each of the droplet discharge heads.
Conventionally, an assembly device is known in which a plurality of droplet discharge heads is positioned on a carriage that serves as a head holder and is fixedly mounted thereon. This assembly device includes a movable table on which the carriage on which the plurality of droplet discharge heads is temporarily mounted, an imaging means to take an image of the positions of the carriage and the droplet discharge heads, fine adjustment means to move the droplet discharge heads, and a fixing processor to secure the droplet discharge heads to the carriage. In this type of assembly device, first, an alignment mask formed by patterning a reference position mark of the carriage and a reference position mark of each droplet discharge head is set on the movable table. Then, the table is moved, the reference position mark of the carriage and the reference position marks of each of the droplet discharge heads formed on the alignment mask are sequentially imaged by the imaging means, and the imaged data is stored as master position data.
Next, the alignment mask is removed from the table of the assembly device, and the carriage on which the plurality of droplet discharge heads is actually, temporarily mounted is set on the table. Then, the table is moved, the imaging means images the position of the carriage to obtain the positional data of the carriage, and the obtained positional data is compared with the master position data to position the carriage. Then, the table is moved, one of the plurality of droplet discharge heads temporarily mounted on the carriage is imaged by the imaging means, so that the positional data of the droplet discharge head is obtained. Based on the obtained droplet discharge head positional data and the master position data, the position of the droplet discharge head relative to the carriage is minutely moved by the fine adjustment means to position the droplet discharge head, and the droplet discharge head is fixedly mounted to the carriage by the fixing processor. The positioning and securing processes are sequentially performed for all the droplet discharge heads temporarily mounted on the carriage, so that each droplet discharge bead is mounted to its corresponding, predetermined position of the carriage.